相关论文: Feathering Instability of Spiral Arms. II. Paramet…

We report the existence of spiral arms in the recently formed gaseous and dusty disk of the closest giant elliptical, NGC 5128 (Centaurus A), using high resolution 12CO(2-1) observations of the central 3 arcmin (3 kpc) obtained with the…

We observed the spiral galaxies M51 and M83 at 20" spatial resolution with the bolometer array AzTEC on the JCMT in the 1.1$\,$mm continuum, recovering the extended emission out to galactocentric radii of more than 12 kpc in both galaxies.…

We describe simulations of the response of a gaseous disc to an active spiral potential. The potential is derived from an N-body calculation and leads to a multi-armed time-evolving pattern. The gas forms long spiral arms typical of grand…

Spiral arm spurs are prominent features that have been observed in extinction and 8$\mu$m emission in nearby galaxies. In order to understand their molecular gas properties, we used the Owens Valley Radio Observatory to map the CO(J=1--0)…

We perform local $N$-body simulations of disk galaxies and investigate the evolution of spiral arms. We calculate the time autocorrelation of the surface density of spiral arms and find that the typical evolution timescale is described by…

Observations of line emission from water masers near the center of the galaxy NGC 4258 have recently provided compelling evidence for rotating disk of gas, viewed nearly edge-on, surrounding a massive black hole (Miyoshi etal. 1995). We…

We have observed a snapshot of our N-body/Smoothed Particle Hydrodynamics simulation of a Milky Way-sized barred spiral galaxy in a similar way to how we can observe the Milky Way. The simulated galaxy shows a co-rotating spiral arm, i.e.…

Spiral arms greatly affect gas flows and star formation in disk galaxies. We use local three-dimensional simulations of the vertically-stratified, self-gravitating, differentially-rotating, interstellar medium (ISM) subject to a stellar…

We applied a criterion of gravitational instability, valid for two-component and infinitesimally thin discs, to observational data along the major axis for 7 spiral galaxies of early types. Unlike most papers, the dispersion equation…

The main goal of this work is to quantify, through a robust methodology, the contribution of invariant manifolds to the formation of spiral arms in a pure N-body simulation, setting up a machinery to perform similar tests in other and more…

Studying star formation in spiral arms tells us not only about the evolution of star formation, and molecular clouds, but can also tell us about the nature of spiral structure in galaxies. I will address both these topics using the results…

Dust trapping accelerates the coagulation of dust particles, and thus it represents an initial step toward the formation of planetesimals. We report $H$-band (1.6 um) linear polarimetric observations and 0.87 mm interferometric continuum…

The density-wave theory of spiral structure proposes that star formation occurs in or near a spiral-shaped region of higher density that rotates rigidly within the galactic disk at a fixed pattern speed. In most interpretations of this…

Stationary density waves rotating at a constant pattern speed $\Omega_{\rm P}$ would produce age gradients across spiral arms. We test whether such age gradients are present in M81 by deriving the recent star formation histories (SFHs) of…

Star clusters provide unique advantages for investigating Galactic spiral arms, particularly due to their precise ages, positions, and kinematic properties, which are further enhanced by ongoing updates from the astrometric data. In this…

We use $^{12}$CO (J=1-0) MWISP data to study turbulence in a segment of the Local Arm. Velocity slices at different kinematic distances show similar spatial power spectra (SPSs) and structure functions (SFs), demonstrating that the entire…

We describe the dynamics of a stream of equally spaced macroscopic particles in orbit around a central body (e.g. a planet or star). A co-orbital configuration of small bodies may be subject to gravitational instability, which takes the…

We carry out three dimensional SPH simulations to show that a migrating giant planet strongly suppresses the spiral structure in self-gravitating discs. We present mock ALMA continuum observations which show that in the absence of a planet,…

We present the numerical study of the formation of spiral structure in the context of violent relaxation. Initial conditions are the out-of-equilibrium disks of self-gravitating particles in rigid rotation. By that mechanism, robust and…

Since the discovery that the majority of low-redshift galaxies exhibit some level of spiral structure, a number of theories have been proposed as to why these patterns exist. A popular explanation is a process known as swing amplification,…